2008 DODGE RAM 5500 CHASSIS CAB overheating

Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Recommended
Fluids and Genuine Parts for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.NOTE:On models equipped with Diesel engines, the
idle speed will automatically increase to 1000 rpm at
elevated coolant temperatures to improve engine cooling.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
UNDERSTANDING YOUR INSTRUMENT PANEL 245
4

STARTING PROCEDURES ± GAS ENGINES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
The starter should not be operated for more than 15-
second intervals. Waiting a few seconds between such
intervals will protect the starter from overheating.
WARNING!
Be sure to turn off the engine and remove the key
from the ignition switch if you want to rest or sleep
in your car. Accidents can be caused by inadvertently
moving the gear selection lever or by pressing the
accelerator pedal. This may cause excessive heat in
the exhaust system, resulting in overheating and
vehicle fire which may cause serious or fatal injuries.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
Manual Transmission ± If Equipped
Apply the parking brake, place the gearshift control lever
in NEUTRAL and depress the clutch pedal to the floor
before starting the vehicle. This vehicle is equipped with
a clutch interlocking ignition system. It will not start
unless the clutch is fully depressed.
Automatic Transmission ± If Equipped
Start the engine with the selector lever in NEUTRAL or
PARK position. Apply the brake before shifting to any
driving range.
252 STARTING AND OPERATING

If the engine has been flooded, it may start to run, but not
have enough power to continue running when the key is
released. If this occurs, continue cranking with the accel-
erator pedal pushed all the way to the floor. Release the
accelerator pedal and the key once the engine is running
smoothly.
If the engine shows no sign of starting after two 15
second periods of cranking with the accelerator pedal
held to the floor, the normal starting procedure should be
repeated.
After Starting
The idle speed is automatically controlled and will de-
crease as the engine warms up.
STARTING PROCEDURES ± DIESEL ENGINES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
The starter should not be operated for more than 15-
second intervals. Waiting a few minutes between such
intervals will protect the starter from overheating.
WARNING!
Be sure to turn off the engine and remove the key
from the ignition switch if you want to rest or sleep
in your car. Accidents can be caused by inadvertently
moving the gear selection lever or by pressing the
accelerator pedal. This may cause excessive heat in
the exhaust system, resulting in overheating and
vehicle fire which may cause serious or fatal injuries.
STARTING AND OPERATING 255
5

Engine Speed Control
CAUTION!
Prevent overspeeding the engine going down hill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.
Operating Precautions
Avoid Overheating The Engine
The temperature of the coolant (a mixture of 50%
ethylene-glycol and 50% water) must not exceed the
normal range of the temperature gauge (240ÉF/116ÉC)
with a 16 psi (110 kPa) radiator cap.
Usually the coolant temperature indicated during opera-
tion will be to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140ÉF/60ÉC) can be
harmful to the engine. Low coolant temperature can
cause incomplete combustion which allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the engine.
Cooling System Tips Ð Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
²City Driving Ð
when stopped, put transmission in neutral and increase
engine idle speed.
²Highway Driving Ð
reduce your speed.
268 STARTING AND OPERATING

reduce the potential for transmission overheating or
failure due to excessive shifting. When operating in
ªTOW HAULº mode, 5th gear is disabled and 2-3 and 3-4
shift patterns are modified. Shifts into Overdrive (4th
gear) are allowed during steady cruise (for improved fuel
economy) and automatic closed-throttle downshifts to
3rd gear (for improved braking) will occur during steady
braking. Pressing the ªTOW HAUL O/D OFFº button a
second time to select O/D OFF will disable 4th and 5th
gear completely, which should eliminate any excessive
transmission shifting.
The ªTOW HAULº or ªO/D OFFº light will illuminate in
the instrument cluster to indicate when the switch has
been activated. Pressing the switch a third time restores
normal operation. If the ªTOW HAULº or ªO/D OFFº
modes are desired, the button must be pressed each time
the engine is started.When To Lock Out Overdrive
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent 4±3±4 transmission shifting
occurs, press the ªTOW/HAULº button twice to disable
the overdrive. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting.
Torque Converter Clutch
A feature, designed to improve fuel economy, has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
high gear. When the vehicle speed drops or during
acceleration when the transmission downshifts to second
gear, the clutch automatically disengages.
278 STARTING AND OPERATING

reduce the potential for transmission overheating or
failure due to excessive shifting. When operating in
ªTOW HAULº mode, 6th gear (if equipped) is disabled
and 2-3 and 3-4 and 4±5 shift patterns are modified. Shifts
into Overdrive (5th gear) are allowed during steady
cruise (for improved fuel economy). Pressing the ªTOW
HAUL O/D OFFº button a second time to select O/D
OFF will disable 5th and 6th gear completely, which
should eliminate any excessive transmission shifting.
The ªTOW HAULº or ªO/D OFFº light will illuminate in
the instrument cluster to indicate when the switch has
been activated. Pressing the switch a third time restores
normal operation. If the ªTOW HAULº or ªO/D OFFº
modes are desired, the button must be pressed each time
the engine is started.WARNING!
Do not use the Tow/Haul feature when driving in icy
or slippery conditions as the increased engine brak-
ing can cause the rear wheels to slide and the vehicle
to swing around with the possible loss of vehicle
control, which may cause an accident possibly result-
ing in personal injury or death.
When To Lock Out Overdrive
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent 6±5±6 or 5±4±5 transmis-
sion shifting occurs, press the ªTOW/HAULº button.
This will improve performance and reduce the potential
for transmission overheating or failure due to excessive
shifting.
284 STARTING AND OPERATING

Operating Tips
Under ideal snow plowing conditions, 20 mph (32 km/h)
should be maximum operating speed. The operator
should be familiar with the area and surface to be
cleaned. Reduce speed and use extreme caution when
plowing unfamiliar areas or under poor visibility.
NOTE:During snowplow usage on vehicles equipped
with an overhead console module, the outside tempera-
ture display will show higher temperatures than the
outside ambient temperature. The higher displayed tem-
perature is due to blocked or reduced airflow to the
underhood ambient temperature sensor by the snow-
plow. This is common and outside temperature display
operation will return to normal when the snowplow is
removed.
General Maintenance
Snowplows should be maintained in accordance with the
plow manufacturer's instructions.
Keep all snowplow electrical connections and battery
terminals clean and free of corrosion.
When plowing snow, to avoid transmission and driv-
etrain damage, the following precautions should be ob-
served.
²Operate with transfer case in 4L when plowing small
or congested areas where speeds are not likely to
exceed 15 mph (24 km/h). At higher speeds operate in
4H.
²Vehicles with automatic transmissions should use 4L
range when plowing deep or heavy snow for extended
periods of time to avoid transmission overheating.
368 STARTING AND OPERATING

In general, the least amount of accelerator pedal pressure
to maintain the rocking motion without spinning the
wheels or racing the engine is most effective. Racing the
engine or spinning the wheels, due to the frustration of
not freeing the vehicle, may lead to transmission over-
heating and failure. Allow the engine to idle with the
transmission selector in NEUTRAL for at least one
minute after every five rocking-motion cycles. This will
minimize overheating and reduce the risk of transmis-
sion failure during prolonged efforts to free a stuck
vehicle.EMERGENCY TOW HOOKS Ð IF EQUIPPED
Your vehicle may be equipped with emergency tow
hooks.
NOTE:For off-road recovery, it is recommended to use
both of the front tow hooks to minimize the risk of
damage to the vehicle.
WARNING!
Chains are not recommended for freeing a stuck
vehicle. Chains may break, causing serious injury or
death.
394 WHAT TO DO IN EMERGENCIES